An arc furnace serves for producing liquid metal, generally steel. The liquid metal is produced from solid melting charge, for instance scrap or reduced iron, together with further additions. For this purpose, at the beginning of the process the arc furnace is charged with scrap and/or reduced iron and possibly further additions or alloying constituents and then at least one arc is struck between at least one electrode and the solid melting charge. The energy introduced into the arc furnace by the at least one arc leads to the melting of the solid melting charge. During the melting process, additives, such as coal or lime, or alloying elements may generally also be fed to the arc furnace.
The melting process in the arc furnace is generally accompanied by acoustic phenomena, since the melting charge inside the arc furnace moves during the melting process. These phenomena may, for example, be caused to varying extents by the burning of the arc, by chemical reactions or else by scrap collapses.
Particularly scrap collapses during the melting process are problematic, since—if there is a correspondingly great moving mass—they can lead to damage or rupture of an electrode in the arc furnace.